August 31, 2014

Pits Cross-Cutting Pits

south up image by Mikhail Abgarian, Yuri Goryachko, and Konstantin Morozov, Minsk, Belarus

This is a magnificent image. You can inspect it scientifically, but first simply admire its sharpness, tonality and beauty. OK, now the science. First, notice the relationship of Eratosthenes with Copernicus, off the image to the right. Although Copernican secondaries crossing Stadius and near the right edge of the image are large and not especially radial, there are smaller, radial lines of secondaries cutting across the southern (upper) and western (right) ejecta of Eratosthenes. Look closely and also notice the faint rays from Copernicus that were deposited across most of the scene. Eratosthenes also has radial chains of secondary craters, best seen to the north on top of Imbrium lavas. Tiny rilles (about 400 m wide), rarely seen from Earth, are visible connecting Eratosthenes D and E and extending north from there. Another disrupted rille occurs near the left edge of the image, hugging the mountainous edge of the Apennines. This is the feature recently speculated to be a continuation of the Bode pyroclastics rille at upper left. This Minsk image suggests to me that a landslide from the mountain just right of Marco Polo L buried the missing center part of the rille. Perhaps gravitational adjustments to the Apennine ejecta deposit were still happening hundreds of millions of years after it was emplaced, and after the mare lavas had erupted.